Suction cleaning nozzles for street cleaning apparatus



J. L. QBERG Dec. 15,1959

Filed Oct. 31. 1955 FIG I I ik United States Patent SUCTION CLEANING NOZZLES FOR STREET CLEANING APPARATUS John Lennart Oberg, Jordholmen, Sweden, assignor to Ab Asbrink & Co.', Limhamn, Sweden, a corporation of Sweden This invention relates to suction cleaning nozzles especially for sweeping of streets and the like.

It has long been imagined that it should be possible to perform the cleaning or sweeping of streets with a cleaning machine operating mainly on the same principle as a vacuum cleaner with suction no'zzle, with the difference, however, that the unit is enlarged and mounted on a vehicle, e.g. a motor vehicle, so that the suction nozzle may be moved by the vehicle over the street surface at a short distance therefrom, said suction nozzle having a sufficiently large working width and a sufficiently large nozzle aperture as well as sucking action to suck up the sweepings from the street surface and convey them by the flowing suction air to a container on the vehicle where they are separated from the air and collected, the container being emptied from time to time. suggestions already made in this direction, some also are to the effect that the suction air can be caused to circulate by putting it under pressure, after the sweepings have been separated therefrom, and blowing it out through a blowing air nozzle surrounding the suction nozzle in order that the blowing air discharged through said blowing air nozzle may loosen up and carry along the sweepings and be sucked up again through the suction nozzle. The many proposals hitherto made to reduce these prior suggestions to practice in a street cleaning machine of sat isfactory function have failed because of the many technical difiiculties met with in this connection. Only lately and with the aid of several new inventions including the present invention it has been found possible to overcome the technical difficulties to such an extent that the possibility of realizing the old suggestions in practice, with the results aimed at, has come within reach.

The object of the present invention is to provide an improved suction cleaning nozzle overcoming one of the many difiicultiesencountered, This difiiculty manifests itself in a strong tendency of the sweepings which are sucked up from the street surface through the suction nozzle and are conveyed by the suction air stream through a conduit to the container for separation and collection, to adhere and collect on the inside of the suction nozzle and the suction conduit, whereby these parts will soon be clogged.

Further objects of the invention and advantages gained thereby will become apparent from the following description, reference being had to the acompanying drawing, in which Fig. 1 is a diagrammatic view illustrating how the present invention is applied to a novel suction and blowing nozzle unit which is the invention of another invento'r and which has proved to operate with satisfactory results in practice when improved by the means of the present invention for eifectively obviating the clogging of the suction nozzle and suction co'nduit, which would otherwise occur very rapidly.

Fig. 2 is a vertical cross section on a larger scale through the nozzle arrangement.

Of the many 2,916,761 Patented Dec. 15, 1959 Fig. 3 is a plan view as seen from below of the nozzle arrangement on a smaller scale.

Figs. 4 and 5 are detail sections.

In the nozzle arrangement illustrated the suction nozzle 1, as seen from below, provides an orifice in the form of an elongate straight slot, and at a distance outwardly from said slot there extends a blowing air nozzle 2 which, as seen from below, provides an orifice in the form of an annular slot surrounding the suction nozzle 1. The o'rifices of the suction and blowing nozzles lie approximately in the same horizontal plane, and above said plane they leave between each other an annular chamber 3 which is open downwardly and has inclined side walls 4 and 5 which extend upwardly and outwardly from the lower end of the nozzle structure. The side wall 4 adjacent to the suction nozzle 1 merges at its lower end with a smoothly curved portio'n 6 (Fig. 5) in the suction nozzle wall, and the outer side wall 5 of the chamber 3 constitutes at the same time the inner wall of the annular blowing nozzle 2. In the transition between the suction nozzle wall and the wall 4 there are spaced water ejecting openings 7 (Fig. 5) leading from a distributing chamber 8 provided around the lower end of the suction nozzle 1 and connected by means of a conduit 9 to a source of water under pressure which, in the form shown, is a water tank 10 mounted on the vehicle and a pump 11 (Fig. 1) in the conduit 9 from said tank. Said conduit 9 branches off also to manifolds 12 which are disposed at the top of chamber 3 in front of and behind the suction nozzle 1 and which are provided with suitably distributed water ejecting openings 13 (Figs. 2-4) directed towards the wall 4.

It has been established that the supply of water through the water ejecting openings 7 and 13 is an eflicient means for preventing the sweepings sucked up from the street surface from adhering and collecting in the suction nozzle and the suction co'nduit leading from said nozzle to the container (not shown) on the vehicle for separating and collecting the sweepings. The invention must not, however, be regarded as restricted to just that location of the water ejecting openings, which is illustrated by way of example on the drawing. It is essential for the location of the water ejecting openings, however, that it be selected in such a way that under the action of the blowing and suction air the ejected water spreads, and sweeps over, the inside of the suction nozzle and the conduit leading from said nozzle to the container for separating and collecting the sweepings. It is advantageous, though not absolutely necessary, that also that portion of the bounding surface of the chamber 3 which lies adjacent the suction nozzle and smoothly merges in the inside of said nozzle, is swept by such a water, which is realized in the form shown and described due to the described arrangement of the water ejecting openings 13. It should be observed that neither the water ejecting openings 7 nor the water ejecting openings 13 have the task of moistening the street surface either before or during the sweeping of said surface by the blowing and suction air.

It will be understood that by reason of the location of the liquid ejecting openings, the air blast from the blowing nozzle 2 will carry the liquid ejected from opening 13 towards the suctio'n nozzle 1 and there join with the liquid ejected from the opening 7 to be drawn into the suction nozzle 1. In this manner, the walls of the suction nozzle are flushed by the combined action of the blowing and suction nozzle.

Ahead of the pump 11 in the conduit 9 there may preferably be inserted a filter 19 (Fig. 1), and in the conduit 9 there may preferably also be interposed a water heater 15 (Fig. 1) in which the water supplied to the water during cold weather. By recirculating water, which has been heated in the water heater 15, through the tank 10, ice formation may be prevented also in said tank and in the conduit leading therefrom.

What I claim and desire to secure by Letters Patent is:

1. In an apparatus for cleaning streets and other surfaces by a suction, a housing through which a central suction passage extends, said passage having a mouth at one end, a water chamber arranged around and encircling the mouth of the suction passage, said chamber including an inclined wall extending angularly and upwardly away from the mouth of the suction passage, said wall being provided with water-outlet openings at its base and adjacent to and extending around the mouth of the suction passage, the housing also including an air chamber into which air under pressure is forced, said chamber having an angularly-arranged outlet opening extending around and encircling and spaced from said inclined wall, waterejection means located between said inclined wall and the air outlet and arranged to direct water under pressure toward said inclined wall, means for supplying air under pressure into the air chamber, and means for supplying water under pressure into the water chamber and to the water-ejection means.

2. An apparatus for sweeping streets and the like by suction, a suction-cleaning nozzle provided with an elongate orifice, a substantially ovate blowing nozzle spaced from and surrounding the suction nozzle, the blowing no'zzle having inner and outer walls which incline upwardly and outwardly from the mouth of the suction nozzle, an annular chamber formed between the nozzles,

and being closed at the top and open at the bottom and having an inner wall formed as a lateral, inclined extension of the suction nozzle and including a smoothly rounded portion located adjacent to the orifice of the suction nozzle, said smoothly rounded portion having water ejecting openings, conduit means connected to said water ejecting openings and extending from a source of water under pressure, said water ejecting openings being so arranged that upon ejection of water through them the ejected water, when acted upon by air being sucked to and through the suction nozzle, will spread on and sweep over the inside of said suction nozzle.

3. In an apparatus for-cleaning streets and the like by suction, a suction cleaning nozzle having an elongated mouth, a blowing nozzle having a mouth encircling said suction cleaning nozzle mouth in spaced relationship thereto, a wall extending between said nozzles and including a portion inclined upwardly from said suction cleaning nozzle mouth, a smoothly curved wall portion joining said portion inclined upwardly from said suction cleaning nozzle mouth, a source of liquid under pressure, liquidejection openings between said nozzles and directed toward said inclined wall portion for supplying liquid to the lower surface of said curved wall, and means connecting said source to said liquid-ejection openings.

4. The structure of claim 3 including liquid-ejection openings at said curved wall directed angularly across said suction cleaning mouth.

References Cited in the file of this patent UNITED STATES PATENTS 584,968 Taylo'r June 22, 1897 1,114,592 De Witt Oct. 20, 1914 2,237,830 Jerome Apr. 8, 1941 2,497,435 Branneman Feb. 14, 1950 FOREIGN PATENTS 732,972 Great Britain July 6, 1955 

